Regulator



E. B. FOOTE REGULATOR July 27, 1937.

Original Filed Dec. 18, 1934 3 Sheets-Sheet 1 fi L M F A mflm m H. MB. 0 a WA m /a 2 y July 27, 1937. E. B. FOOTE 2,088,055

REGULATOR Y Original File d D96. 18, 1934 3 ShBGtS-SIIOGt '2- fill? SUPPLY ATI'ORNEY 'E. B. Foo-re July .27, 1937.

REGULATOR 3 Sheets-Sheet 3 Original Filed Dec. 18, 1934 INVENTOR EDWARD B. Foam:

ATTORN EY Patented July 27, 1937 UNITED STATES PATENT OFFICE? REGULATOR Application December '18, 1934, Serial No. 758,088

. Renewed June 25, 19,36

12 Claims. (Cl. 236-82) This invention relates to regulating systems and more particularly to recording regulators.

The main feature of the invention. relates to a regulating device, the sensitivity of which is universally adjustable over a wide range, the adjustments being effected without disassembling any part of the mechanism.

Another feature of the invention relates to the construction of a recording regulator in which the drag on the pen or stylus has been greatly reduced at all sensitivities and at cert'ain sensitivities has been reduced to a negligible amount.

An additional feature relates to, a regulating device which can be readily changed from a direct-acting to a"reverse-acting device, merely by rearranging certain of the parts of theoperating mechanism-and not by the addition of parts. 3

Still another. feature of the invention relates to a simple regulating unit that can be used as a portion of a more complex instrument, in which the control point in the medium-to be regulated is automatically changed or reset in accordance with a change in a condition outside of said medium.

A further feature of the invention relates to improvements in direct ratio and inverse ratio reset regulating devices.

The various features and advantages ,of the invention willappearfrom the detailed descripof a portion of the construction illustrated in Fig. 5, showing how the direct ratio reset instrument there shown can have its parts rearrangedto provide an inverse ratio reset regulator.

Referring especially to Fig. 1, 5 designates a thermo-sensitive bulb which is connected by a capillary tube 6 to a Bourdon spring I. The bulb 5, tube 6 and spring I constitute a tube system which may be filled with any suitable expansible medium, such as a liquid, a vapor or a combina-' tion of both. One end of the Bourdon spring is fastened by the spring mounting 8 to the frame ofthe instrument, while the free end of the spring is connected by a link. 9 to the bracket iii of a' pen arm II, which bracket has itsstaff l2 journaled in a suitable supporting column or pillar generally designated I 3 (Fig. 2). The free end of the pen arm II is provided with a pen or stylus M which traces a curve corresponding to the changing temperature sensed by the medium a in the bulb 5, the curve being traced on a graduated chart [5 rotated in accordance with time by a clock of which only arbor i6 is illustrated.

arms of bracket 20, being held in position by the pivot screw l9a (Fig. 6) The lever ID has mounted thereon, an adjustable. rotatable disc 2I provided with an eccentrically mounted stud tion and claims when taken with the drawings in. Z2 projecting toward the back of the instrument. which Fig. 1 is a plan view of the mechanism gfillg disc may be frictionally held in its adjustedof a simple recording regulator of the present invention; Fig. 1a. is a plan view of a plate which may be used in the device to change it from one utilizing a sensitivity reducer to one that does not employ that principle of operation; Fig. 2 is a side elevation of a'pillar construction for mounting the pen "arm brackets illustrated in Fig. 1; Fig. .3 is a fragmentary plan view of a, portion of the structure shown in Fig. 1, illustrating howthe device may be changed from a direct-acting to a reverse-acting regulator; Fig. 4 is a plan view of a recording regulator and a diagrammatic showing of a portion of the regulating system in-which it is incorporated; Fig. 5

. is a somewhat enlarged plan view .of the actuating' mechanism of theregulator of Fig. 4; Fig. 6 is a cross-sectional view'thereof taken substantially on the line 6-6 of Fig. 5 with a por-. tion of the pillar construction; Fig. '7 is a side elevation of a portion of the structure shown in Fig. 5; Fig. 8 is a topv view thereof partially in section; and Fig. 9 is a fragmentary disclosure position by suitable screws Ma. also shown in Fig.6. It will be understood that the rotation of the disc 2| changes the'adjustment of thestud 22 with respect to the baffle by a clockwise or a counterclockwise movement, as desired. A set lever 23 is likewise pivoted on the pivot stud a of bracket 20 beneath the lever It, the pivot stud and pivot i9 being in axial alinement. The upper end of this set lever is provided with teeth to form a sector gear 24 which is arranged to be driven by a gear train comprising gears 25, 25a and 25b. The square headed staif 26 of the gear 25- may be rotated by an adjusting key (not shown) to drive the mentioned gear train which actuates the sector gear 24 so that set lever 23- can be rotated clockwise or counterclockwise, as desired, about pivot stud No as an axis. A link 21' connects the upper end of the set lever to the stafi 28a of the bracket 28 of a set point indicator S. This staff is rotatably mounted in the supporting column l3 as indicated in. Fig. 2 with its axis in alinement with the axis of the staff 4| thus serves as a sensitivity reducer.

l2 of the pen arm bracket. It will be understood that as the set lever 23 is rotated about the pivot stud 20a in response to the actuation of the train of gears, the set point indicator S will be moved to indicate, in cooperation with the chart |5, the temperature that it is desired to maintain through the regulation by the present instrument.

On the lever 23 there is mounted for longitudinal movement a sliding plate 29 provided at one side with a rack 30. This plate is limited to sliding movement by a pin 23a .on the set lever which engages the edge of the plate opposite the rack and by a stud 34 (Fig. 6) mounted on the plate which stud engages the sides of slot 34a in the set lever with a. very close fit to prevent lost motion between the stud and the lever. A pinion 3|, rotatively mounted on the set lever 23 opposite the pin 23a, engages the rack teeth formed on the plate 29 while the stub shaft 32 of this pinion is slotted so that it may be rotated by means of a screw driver to move the plate 29 lengthwise to change the sensitivity of the instrument. By this construction the unit sensitivity ofthe regulator can be readily adjusted or matched with respect to the time lag of the regulated process to afford steady action at the motor diaphragm valve. The term unit sensitivity as herein employed, is the distance of the control pen travel on the chart, necessary to cause a 10 lbs. air pressure change on the diaphragm motor valve V. In this description reference is made to a high and low unit sensitivity, high sensitivity being arbitrarily takenas the range of approximately 6 to approximately pen travel for a 10 lbs. air pressure change, and low sensitivity being arbitrarily taken as 1 1; to approximately 5" pen travel to effect a 10 lbs. pressure change. It is preferred to mount a graduated disc 33 on the shaft 32 for movement relative to an indicating mark 33a on the lever 23 to indicate difierent positions of sensitivity adjustment. The reduced end 35 (Fig. 6) of the stud 34 serves as a pivot for baffle 36. This baffle is provided with a right angular arm 31 having at its free end a counterweight 38 so positioned that the upper end of the baffle normally tends to move counterclockwise toward the stud 22 and the lower end thereof tends to move toward a nozzle 39 to control the escape of pressure fluid.

The nozzle 39 is mounted on the face 49 of a flexible bellows or capsular diaphragm 4|, theother face 42 of which is permanently mounted on a block 43 attached to the setlever 23. The orifice in the nozzle communicates through conduit 44 and the passage 45 in the block 43, with the conduit 46 which, in turn, commlmicates with a source of fluid pressure such as compressed air flowing through the constriction 46a. Conduit 46 also leads to the diaphragm 52 of the relay valve 53. It will be noted that the block 43 is also connected by a branch conduit 41 communieating with the conduit 6| leading from the relay valve 53 to the diaphragm of the motor valve V, to be regulated. This block also has a passageway 48 which communicates with a groove 49 in the plate 56 and thence through the passageway 5| to the capsular diaphragm 4 The diaphragm Under certain conditions of regulations when a high sensitivity adjustment is desired, the plate 50 is reversed end for end from its position, as shown, so that pressure fluid is prevented from flowing from the passageway 48 to the passage 5| and thence to capsular diaphragm 4| .whereby this diaphragm is thus rendered ineffective and consequently no sensitivity reduction is efiected thereby. I

The instrument as shown in Fig. 1 is of the direct-acting type, that is, it operates on a rising temperature to cause the motor diaphragm valve V to close. In the operation of the regulating system as disclosed in this figure, let it be assumed that the temperature about the bulb 5, rises and in consequence thereof it is desired to close the diaphragm valve V which regulates the flow of steam through pipe 54 for heating the material about the bulb 5. In response to this increase in temperature, the filling medium within the bulb 5 expands, thereby causing the Bourdon spring I to unwind. As a result of this unwinding movement, the link 9 moves the bracket ID of the pen arm clockwise, thereby moving the pen arm and its stylus to make a record of the temperature change on the chart I5. The pen arm bracket Ill and its staff move the link H to swing the bafile-actuating lever I8 in a clockwise direction. If the temperature isnow above the control point of the instrument, that is, the temperature indicated by the set point indicator S, the stud 22 on this lever swings the baflie 36 clockwise about its .pivot 35 with the result that the lower end of the bafiie moves away from the nozzle 39. The pressure in the conduits 44 and 46 connected to the nozzle 39 thereupon decreases causing the diaphragm 52 of the relay valve 53 to contract and to open this valve. The opening of this relay valve permits pressure fluid to flow through conduit 6| to the diaphragm of the motor valve V in the steam supply line 54, thus tending to close this motor valve.

In the event that the temperature about the bulb 5 falls, the filling medium therein will contract and the Bourdon spring I will tend to wind up. As a result of this movement,v the link 9 moves the bracket ll] of the pen arm counterclockwise. The pen arm bracket l9 moves the link I! to swingthe bafile-actuating lever in a counterclockwise direction. If the temperature about the bulb 5 is below the control point of the instrument, the stud 22 on the lever l8 recedes from the baflie 36 permitting the counterweight 38 thereon to swing the baflle 36 counterclockwise about its pivot 35 so that the lower end of the bafiie moves toward the nozzle 39. The pressure in the conduits 44 and 46 connected to the nozzle 39 increases, with the result that the diaphragm 52 and the relay valve 53 expands to closethis valve. The closing of the relay valve cuts off pressure fluid to the conduit 5| leading to the diaphragm of the motor valve V in the steam supply line 54 so that the motor valve tends to open.

The instrument as shown in Fig. 1 is arranged to have low sensitivity and as a result of this arrangement an increase in the flow of pressure fluid through conduit 6| to the motor valve V on a rise in temperature at bulb 5, increases the flow of pressure fluid in conduit 41, this pressure fluid, in turn; flowing through the passage 48, groove 49, passage 5|, to the interior of the capsular diaphragm 4|. The pressure fluid thus introduced into this diaphragm causes it to expand, with the result that the nozzle 39 follows gradually in the direction of the moving baffle thereby causing the reduction in pressure of the fluid in conduit 46 to be more gradual and the operation of the relay valve 53 to take place more slowly so that the sensitivity of the instrument is reduced. Conversely, a drop in pressure in conduit 41 causes the nozzle to recede from the baffle.

In the event that it is desired to change the sensitivity adjustment of the instrument, the

pinion 3| is rotated by a screw driver inserted in the kerf in the exposed end of the pinion shaft 32. The rotating pinion 3| meshes with the rack on the plate 29 to raise or lower this plate, depending on the direction of rotation of this pinion. It will be noted that as the plate 29 is moved upward by a counterclockwise rotation of pinion 3| to increase the sensitivity of the instrument, the upper arm of the baffle 36, that is, the portion between the pivot and the stud 22 is shortened, where-as the lower arm of the baffie between pivot 35 and the point where the baiile engages the orifice in the nozzle, is effective.- ly lengthened. A clockwise rotation of pinion 3i reverses these conditions, that is, increases the length of the upper arm and decreases the length .of the lower arm of the baffle, thereby reducing the sensitivity of the instrument. .By this construction it is possible to have uniform progressive adjustment of the sensitivity of the instru-.

ment throughout a wide range of settings. It will be understood that as the sensitivity of the instrument is reduced, the upper arm of the bafile increases in length thereby reducing the effect of the counterweight 38 on the Bourdon spring and consequently reducing the resulting motion of the pen I4, that is, the pen drag. If it is desired to change the set point of the indicator, a key (not shown) is applied to the square-headed staff '26 of the gear 25 of the train of gears, which gear train actuates sector gear 24 formed on the end of set lever 23 to swing this lever in either direction as desired. It will be recalled that the link 21 connects this plate to 'the bracket 28 of the set point indicator S so that as the lever is adjusted, this indicator is moved over the chart l5 to indicate the control temperature to which the instrument is being adjusted.

In Fig. 3 a fragment of the instrument is illustrated with its parts rearranged for reverseacting operation. The arrangement of parts of this changed instrument is the same as that' shown in Fig. 1, except that bracket 20 with the pivot stud 20a and pivot screw Ha, has'been mounted in a different position on the frame. It will be noted. that the pivot screw l9a now supports the pivot 19b (Fig. 6) mounted-at an intermediate portion of the baflle actuating arm and the pivot stud 23a pivotally engages an intermediate portion of the set lever 23.. In this arrangement all movements of the bafiie are now reversed with respect to those previously described, so that a rising temperature at the bulb 5 will" result in the operation of the relay valve 53 to shut off the pressure fluid flowing to the diaphragm motor valve V, thereby opening it. This is due to the -fact that the baifle actuating lever I8 on a rising temperature will move the actuating stud 22 away from the baiile 36, instead of moving this stud toward the baffle as in the arrangement of Fig. 1. However, in the case of a falling temperature at' the bulb'5, relay valve 53 will permit pressure fluid to flow to the set lever 23 are located at different positions as above described.

The mechanism disclosed'in Fig. 1 is also par- I ticularly useful as a unit of a direct-ratio reset type of instrument in which one bulb or thermosensitive element 5 adjusts the control point or desired temperature to be maintained by the remainder of the instrument mechanism which includes a second thermosensitive element 75. For example, in certain installations it is desirable to control the temperature in aroom in a certain predetermined relation with respect to the temperature prevailing outside of this room, as for instance when the outside temperature is hot it may be desirable to raise the control point of the instrument to. maintain the temperature within the room at a somewhat higher value, whereas when the outside temperature is cold it may be desirable to lower the control point of the instrument to maintain the temperature within the a to 8 wherein there is illustrated a thermosensitive bulb 5. capillary tube 6 and a Bourdon spring I similar to that already described. It will be understood that this bulb is to be placed in the room or compartment wherein the temperature is to be regulated. The free end of the Bourdon spring 1 is connectedby a link 9 to the bracket I!) of the pen arm II which bracket has its staff l2 pivoted in the column l3 of Figs. 2 and 6. In the present instance the pen arm bracket has attached thereto an arm 10 (Fig. 5), the'lower end of this arm being connected by a link H to the lower end of lever 12 which is pivoted at 13 on a swingable arm 83 movable about the pivot reset automatically the control point of the instrument to maintain a predetermined relation between the regulated condition at bulb 5 and the prevailing condition at the bulb 15, instead of utilizing the manual adjustment of the set point lever 23 .to change the control point and also the position of the set point indicator S as in the instrument of Fig. 1. On this reset type of instrument, the manual adjustmentincluding the gear train 25, is utilized to change the point of control independently of the automatic reset. The bulb l5 communicates through a capillary tube 16 with a Bourdon spring 11, the fixed end of which spring is mounted at 18 on the frame of the instrument. The free end of the Bourdon Spring is connected by a link 19 to the bracket of a second. pen arm 80, likewise mounted on I a pivot with its axis in alinement with the axis of the staff l2. As best shown in Fig. 5, the

bracket of the pen arm (Fig. 4) is provided with an extension 8| (Fig. 6). This extension at an intermediate point thereon is pivotally connected by a link 82 tothe swingable arm 83,

which it will be recalled is pivoted at I4 and which carries the fulcrum 13 for the portion of the linkage that actuates the bathe-actuating arm I8. The operation of the reset regulator is as follows: If the temperature at the bulb 5 rises, the filling medium in the tube system expands causing the Bourdon spring. I to unwind. The link 9 connected thereto is thus moved toward the left causing the pen arm bracket l0 and its attached arm I0 to swing in a clockwise direction. The link (I is connected to the lower end of the arm I0 and lever I2 so that the swinging movement of this arm I0 effects a corresponding clockwise swinging movement of lever I2 about the pivot I3. The swinging movement of the lever I2 which has its upper end connected by link II to the upper portion of the bafile-actuating lever l8, causes a corresponding swinging movement of the lever l8 so that the balile 36 is moved away a corresponding amount from the nozzle 39. The effect of the varying relation between the nozzle and the baffle on the valve V is the same as .that described in connection with the instrument of Fig. l and need not be further described. A drop in temperature about the bulb 5 effects a similar operation of the parts of the instrument, but in the reverse sense.

,If the temperature about the bulb I5 rises, the filling medium therein will cause the Bourdon spring 11 (Fig. 4) to unwind. This motion of the spring 11 causes the link I9 to swing the bracket of pen arm 80 in a clockwise direction. Link 82 connecting this bracket and arm 83 is actuated by this bracket to swing arm 83 ina counterclockwise direction to move the pivot 13 on which lever I2 is mounted, toward the left. Such a movement causes lever I2 to turn clockwise about pivot 13:: (Fig. 5), thus imparting movement to link II and lever 18 so that battle 36 is moved nearer to the nozzle 38. As a result of this relatlve' movement of the baflle and nozzle, valve V opens as described in connection with Fig. 1, increasing the temperature at bulb 5 and causing Bourdon spring I to unwind. This movement is transmitted to baille 36 as described but in the opposite direction from that caused by Bourdon spring 11, thus restoring the baille and nozzle to a control relation but at a higher temperature equivalent.

In order to change the ratio adjustment of the direct ratio reset instrument, the parts 8| (1 and 88a are moved along their respective levers 8| and 8I,'thus changing the distance between pivots I4 and 14b.

In the fragmentary view of Fig. 9 certain of the parts of the direct ratio reset instrument of Figs. 4 to 8 have been rearranged to change that instrument into one of the inverse ratio reset type. The expression inverse ratio" is used to mean that the controlled temperature, changes in the opposite sense from the setting temperature. In this rearranged instrument the bracket plate, 88 and the pivot I4 carried thereby are mounted in a different position in the case (not shown in this figure), the pivot 14 and its supporting plate being disconnected from the lower end of arm 88. Also the pivot clip support 88a and the arm section Me with link 82 are removed from intermediate portions of arms 83 and 8| and are then attached respectively to the lower ends'of these arms so that these ends will be connected by link 82.

The operation of this inverse ratio reset instrument is similar to that of the direct ratio type except that on a rise in temperature at bulb I5 the pivot I3 is moved toward the right so that the control point is lowered. In other words, as the temperature rises at bulb I5, bulb 5 maintains the controlled temperature at a lower value. On a drop in temperature at bulb I5, the pivot I3 is moved toward the left so that the control point is raised and the controlled temperature is maintained at a higher value.

To change the ratio adjustment of the inverse ratio reset instrument, bracket 84 carrying pivot I4 is moved along lever 83 thus changing the distances between pivot I4 and the end pivots I3 and I40.

While the present instrument has been described with particular reference to the regulation of temperature, it is equally applicable to the regulation of pressure, fiow, liquid level and like variable conditions.

I claim:

1. In a regulating system, a pressure fiuid operated motor valve arranged to control the flow of a regulating medium to maintain a predetermined condition, means for controlling the supply of pressure fluid to the motor of said .valve and the discharge of fiuid therefrom, said means including a nozzle having an orifice and a movable bafile cooperating with said orifice,

mechanism including an element responsive to variations in said condition and operatively associated with said baffle to vary the relation of the same with respect to said orifice in accordance with said variations, and single means for adjusting by small increments of movement over a wide range of adjustment the position of :7

said baffle to change the effective length thereof withrespect to said orifice, and with respect to said mechanism.

2. In a regulating system, a pressure fluid operated motor valve arranged to control the flow of a regulating medium to maintain a predetermined condition, means for controlling the supply of pressure fluid to the motor of said valve and the discharge of fluid therefrom, said means including a nozzle having an orifice and for adjusting said baffle tochange the effective length thereof with respect to said orifice by small increments of movement over a wide range of adjustment.

3. In a regulating system, a pressure fluid operated motor valve arranged to control the flow of a regulating medium to maintain a predetermined condition, means for controlling the supply of pressure fluid to the motor of said valve and the discharging of fluid therefrom, said means including a nozzle having an orifice and a baflle cooperating with said orifice, said nozzle and said bafile being carried by a common ad- Justable support, an element actuated in response to variations in said condition and engaging said baille to vary the relation of the same with respect to said orifice in accordance with said variations, means including a reduction gear train for adjusting said support with respect to said element to establish a new predetermined condition, and means for. changing the effective length of said baffle with respect to said orifice by small increments of movement over a wide rangeof adjustment.

4. In 91 regulating system, a pressure fluid operated motor valve arranged to control the flow ofaregulating medium to maintain a predetermined condition, means for controlling the supply of pressure fluid to the motor of said valve and the discharge of fluid therefrom,said means including a nozzle having. an orifice and a movable baffle cooperating with said orifice, a movable arm provided with a part engaging said baffle, means responsive to variations in said condition and. operating said arm to control said baflle to vary the relation of the same with respect to said orifice in accordance with said variations, and sing'lemeans for changing the effective length of said baiile with respect to said orifice and with respect to said part by small increments of movement over a wide range of adjustment.

' 5. In a regulating system, a pressure fluid operated motor valve arranged to control the flow of ,a regulating medium to maintain a predetermined condition, means for controlling the supply of pressure fluid to the motor of said valve and the discharge of fluid therefrom, said means including a nozzle having an orifice and a battle cooperating with said orifice, a movable arm provided with a projection engaging said baflle, said bafile being pivoted between said projection and said nozzle to define two baille arms, means responsive to variations in said condition for operating said arm and projection to control said bafiie in order to change the relation of the same with respect to said'oriflce in accordance with said variations, and single means for proportionally varying the lengths of said baflle arms by small increments of movement.

6. In a regulating system, a pressure fluid operated motor valve arranged to control the fiow of a regulating medium to maintain a predetermined condition, means for controlling the supply of pressure fluid to the motor of said valve and the discharge of fluid therefrom, said means including a nozzle having an orifice anda pivoted bafiie cooperating with said orifice, a counterweight supported on an arm projecting from said baffle adjacent the pivot whereby said baffle tends to swing with respect to said nozzle, a movable arm provided with a projection engaging said baffle, said bafile' being pivoted between said projection and said nozzle to define two b-afile arms, means responsive to variations in said condition and operating said arm and projection to control said bafile in order to change the relation of the Y same with respect to said orifice in accordance with said variations, and single means for proportionally varying the effective lengths of said baflle arms by small increments of movement.

7. In a regulating system a pressure fluid operated motor valve arranged to control the flow of a regulating medium to maintain a predetermined condition; means for controlling the supply of pressure fluid to the motor .of said valve and the discharge of fluid therefrom, said'means including a nozzle having an orifice and a baflle cooperating with said orifice, a movable arm provided with a'part engaging said bafile, a pivot on said arm 'at each side of said part, a pivot support transferable from one pivot to the other to change the regulation effected by said system from direct action to reverse action, means responsive to variations in said condition and operating said arm and part to control said baifle in order to change the relation of the same with respect to said orifice in accordance with said variations, and means for changing the effective small increments of movement over a wide range of adjustment.

8. In a regulating system, a pressure fluid operated motor valve arranged to control the flow of a regulating medium to maintain a predetermined condition, means for controlling the supply of pressure fluid to the motor of said valve and the discharge offluid therefrom, said means including a nozzle having an orifice and a bafile cooperating with said orifice, a movable arm provided with a part engaging said baflle, said arm being arranged to be pivotally mounted at either of two points. thereon at opposite'sides of said part, pivotal mounting means for said arm transferable 'from one 'of said points to the other to change of movement over a wide range of adjustment.

9. In a regulating system, a pressure fluid operated motor valve arranged to control the flow of a regulating medium to maintain a predetermined condition, means for controlling the supply of pressure fluid to the motor of said valve and the discharge of fluid therefrom, said means includ ing a nozzle having an orifice and a baffie cooperating with said orifice, a baflie supporting lever arranged to be pivotally mounted at either of two spaced points thereon, a movable arm provided with a part engaging said baflle, said arm being arranged to be pivotally mounted at either of two points thereon at opposite sides of said part,'pivotal mounting means for said lever and said arm transferable from one pair of points to the other pair to change the regulation effected by said system from direct action to reverse action, meansresponsive to variations in said condition and operating said arm and part to control said baille in order to change the relation of the same with respect to said orifice in accordance with said variations and means for changing the effective length of said baffle with respect to said orifice by small increments of movement over a wide range of adjustment. 1

10. In a regulating system, a pressure fluid operated motor valve arranged to control the flow of a regulating medium to maintain a first condition in a definite relation to a second condition, means for controlling the supply of pressure fluid length of said baflle with respect to said orifice by to the motor of said valve and the discharge of fiuid therefrom, said means including a nozzle having an orifice and a movable bafile cooperating with said orifice, means responsive to variations in said first condition and to variations in said second condition, said means being operatively associated with said baffle to vary the relation of the same with respect to said orifice in accordance with said variations, and mechanism for adjusting by small increments of movement over a wide range of adjustment, the position of said baffle to change the effective length thereof with respect to said orifice.

11, In a regulating system, a pressure fluid operated motor valve arranged to control the fiow of a regulating medium to maintain afirst condition in a definite relation to a second condition, means for controlling the supply of pressure fluid to the motor of said valve and the discharge of fluid therefrom, said means including a nozzle having an orifice and a movable bafile cooperating with said orifice, means responsive to variations in said first condition and to variations in said second condition, said means being operatively associated with said battle to vary the relation of the same with respect to said orifice in accordance with a direct ratio between said variations jointly, and mechanism for adjusting by small increments of movement over a wide range of adjustment, the position of said baflle to-change the effective length thereof with respect-to said orifice.

'12. In a regulating system, a pressure fluid operated motor valve arranged to control the flow of a regulating medium to maintain a first condition in a definite relation to a second condition, means for controlling the supply of pressure fluid to the motor of said valve and the discharge of fluid therefrom, said means including a nozzle having an orifice and a movable baflle cooperating with said orifice, means responsive to variations in said first condition and to variations in said second condition, said'means being operatively associated with said bafile to vary the relation of the same with respect to said orifice in accordance with an inverse ratio between said variations jointly, and mechanism for adjusting by small increments of movement over a wide range of adjustment, the position of said baiile to change the effective length thereof with respect to said orifice.

- EDWARD B. FOOTE. 

